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KCET2022MathematicsProbability

Find the mean number of heads in three tosses of a fair coin.

Options

  1. A1.5
  2. B4.5
  3. C2.5
  4. D3.5

Correct answer

A. 1.5

Step-by-step solution

Given three coins are tossed. Therefore, sample space, S= T T T, T T H, T H T, H T T, H H T , HTH, THH, HHHH n(S)=8 Let X represents 'number of heads' X=0,1,2 or 3 . Probability distribution of X is aligned Required mean & = X_i P_i & =0 ( 1 8 )+1 ( 3 8 )+2 ( 3 8 )+3 ( 1 8 ) & =0+ 3 8 + 6 8 + 3 8 = 12 8 =1.5 aligned

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